What Is Subnetting
By: Dennine Queen
Professor Melanie Howard
Intro to Networking CIS 175
Due: August 15, 2010
What is Subnetting Page 2
What is Subnetting?
The purpose of this paper is to explain subnetting and why it is needed.
If you have a network that has an excessive amount of traffic and is starting to run slowly, you
need to find a way to solve this problem. One of the most effective techniques to solve this problem is
by subnetting.
Subnetting is a technique for breaking a big block of IP addresses into smaller blocks that can
be used to define separate networks. By subnetting a network administrator can enhance security,
improve performance and simplify troubleshooting. One of the main reasons of subnetting is
to help relieve congestion. Congestion was a big problem at one time because it was more common to
use hubs.
Before you subnet you need to sit down and figure out what needs to be subnetted; without
planning and knowing exactly what you are doing you could cause more harm than good. When you
are ready make sure that your subnet structure is the same as your network 's geographic structure.
When subnetting make sure that it is linked through a router and each subnet should have its own hub
or switch.
When you subnetting you need to have a understanding of IP address. Each address is a 32 bit
number that is divided into 4 sections of 8 bits that are called octets. Each octet is converted from
binary to decmial form and separated with a dot to make it easier to read. As an example suppose you
have a Class C block of IP addresses and the address for that block is 38.9.211.0 Since this is a class C
subnet your default subnet mask would be 255.255.255.0. The network portion always remain fixed
for a particular network, while the remaining bits which make up the host portion can be altered to
give the range of addresses to assign
References: http://www.windowsnetworking.com/articles_tutorials/Subnetting-Increase-Performance.html Subnetting to Increase Performance http://www.support.psi.com/support/common/routers/files/SUBNET-Desc.html Subnetting – What, When and How ----------------------- Mask: 255.255.255.0 = 11111111.11111111.11111111.00000000 IP: 38.9.211.0 = 00100110.00001001.11010011.00000000